Can you explain what exactly happens in this block? I don't get a clear explanation of what "xEF\xBB\xBF" means in the below code and why it is having drop ()? . <Exec> if $raw_event =~ /^(\xEF\xBB\xBF)?(date-time,|#)/ drop(); else { csv_parser->parse_csv(); $EventTime = parsedate(${date-time}); } </Exec>

I am trying to use the multlog module in order to start ingesting a custom log: I have the following regex: \^(\d{2}|\d).(\d{2}|\d).(\d{4})\s(\d\d|\d):(\d\d|\d):(\d\d|\d)\s(AM|PM).\[(.*)\](.*) This works in a regex test; however I cannot get it to work with the log file that looks something like this 9/10/2015 11:29:16 AM [0-3-1-SecondaryPortStatus.cs-17] GetStatus for IP: 192.168.0.231 on port: 5016 9/10/2015 11:29:16 AM [0-3-1-SecondaryPortStatus.cs-47] <TRANSACTION> <FUNCTION_TYPE>SECONDARYPORT</FUNCTION_TYPE> <COMMAND>STATUS</COMMAND> <MAC_LABEL>P_061</MAC_LABEL> <MAC>az4FMuLbvrPz720bBeKWz3c+zBh6MsKVo4nJEW96B04=</MAC> <COUNTER>217</COUNTER> </TRANSACTION> 9/10/2015 11:29:16 AM [0-3-1-SecondaryPortStatus.cs-57] <RESPONSE> <RESPONSE_TEXT>Operation SUCCESSFUL</RESPONSE_TEXT> <RESULT>OK</RESULT> <RESULT_CODE>-1</RESULT_CODE> <TERMINATION_STATUS>SUCCESS</TERMINATION_STATUS> <COUNTER>217</COUNTER> <SECONDARY_DATA>10</SECONDARY_DATA> <SERIAL_NUMBER>285498613</SERIAL_NUMBER> </RESPONSE> 9/10/2015 11:29:16 AM [0-1-1-LandingPage.xaml.cs-49] POS opened However when running the nxlog.conf for this I am getting the following error  2015-09-15 08:00:43 ERROR couldn't parse expression at line 12, character 13 in C:\Program Files (x86)\nxlog\conf\nxlog.conf; invalid character: '\' I am unsure what i need to do in order to get this correct; does anyone have any insight or resources I should further explore. Is there a REGEX specific doc for NXLOG?